Also, I've searched online and found several hits for keychain power banks starting at around 2200mAh, which would be good for about a 2/3 charge of a Note 3. Maybe something to consider and keep you charged until you can get connected to a power source.
Let us know what you find and how it works if you decide to purchase something.
It's "OK" but it has a weird issue. It's documented all over the internet but it will stop charging randomly... even though there's more juice in the power pack. I'll have to keep plugging it back in several times to eventually dissipate the battery. While it does get me out of a pinch, I was looking for something a little more reliable and with a bit more power. This one only has 1000maH.
This one having the keyring makes it super easy to carry around. I refuse to carry a separate device just for charging. The keyring charger is a great concept.. i just wish there were more choices.